Electric-arc lamp.



R. HOLSTEN.

` ELECTRIC ARC LAMP.

APPLICATON FILED MAR. 7, |910-l I 1,159,383. Patented Nov. 9, 1915.

, y NvawToR YVTNEQES Rgafuni Halsan I l I i7 dffbrnes UNITED STATES PATENT OFFICE.

RICHARD HOLSTEN,

0F GHARLOTTENBURG, GERMANY, ASSIGNOR T0 SIEMENS- SCHUCKERTWERKE G. M. B. H., 0F BERLIN, GERMANY, A CORPORATION GERMANY.

ELECTRIC-ARC LAMP.

Patented Nov. 9, 1915.

y Application filed March 7, 1910. Serial N o. 547,824.

To all whom t may concern:

Be it known that I, RICHARD HoLsTnN, a subject of the German Emperor, and residing at Charlottenburg, near Berlin, Germany, have invented certain new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

My invention relates to electric arc-lamps, whose arcs are not maintained by electrodes in the form of rods, but by solid, liquid or aseous substances which are supplied in the orm of powder, vapor or gases to between electrodes serving substantially only for supplying the current;

It has long been known in the art that the arc in electric arc lamps may be .maintained by supplying solid combustibles in powder form', or liquid combustibles betweentwo solid and stationary electrodes. The reason Why lamps of this character have not been used more frequently in practice appears to be that in such lamps, as heretofore used, the combustible is supplied by certain mechanisms which, however, respond only to the fluctuations of the current. the supply of combustibles is not proportional to their consumption, which latter aside from being dependent upon the fluctuations of the current,.depends upon several other conditions, affecting and varying the temperature of the arc and thus the degree of vaporiization of fuel. One of these conditions isv the motion of the surroundingair, another the chemical uniformity of the mixture of combustibles supplied to the arc which cannot be completely maintained, however careful the material may be prepared. In view of these above facts, I particularly consider it a disadvantage to have both the electrodes fixed, and the conveying `of combustibles controlled by the iuctuations of current as has been done heretofore. The principal object of my invention is to remedy these defects.

According to my invention, at least one electrode is to be movable-for instance in the form of a suspended solenoid core-to have the well known regulation in dependence on the fluctuations of current or voltage. Thus in particular allthe disadvanltages of lamps with lixed electrodes are In such lamps avoided, owing to irregular supply of combustible and to irregular evaporation of the latter.

According lto my invention the combustible is preferably supplied in dependence on the electrical occurrences. This can be done by mechanically or electromagnetically releasing the feeding device. not possible thereby to avoid under-feed of combustible, for not all the fluctuations-of current and voltage are due to varying consumption of combustible. In the case of over supply either too much combustible is consumed or insulating residues are formed which render re-ignition diiicult; also, combustible which is left lying on one electrode may prevent the electrodes contacting with each other and, consequently, the restriking of the arc. When too little combustible is supplied, on the contrary, the arc is too small and emits too little light. I avoid these defects by supplying the combustible according to its consump-^ tion. Such a regulation is obtained, for example by supplying the combustible at definite intervals. The irregularities, caused thereby are only smalland are readily equalized by the lamp.

Th perfect, however, when it is in dependence on the length of the arc. It is then made dependent on a quite definite position of electrode. This mode of regulation com- However, it is e supply of combustible will be most bines the advantages of the two above described methods of regulation; for the length of arc is dependent both on the existing voltage and on the electrical conditions, f

. elevation showing part of one form of lamp comprising superposed electrodes, the upper rof which is movable and serves as conduit for the combustible; Fig. 2 is a like view showing part of a modified form, in which the combustible is supplied in a lateral tube, Fig. 3 shows in more or less diagrammatical form partly in sectional elevation and partly in perspective another form of lamp, in which two kinds of combustible are supplied to between the electrodes with the aid of the devices shown in Figs. l and 2.

lReferring to the drawings, in all the views A designates the bottom electrode, B the topelectrode, C the regulating coil requisite for the lamp and which may have any suitable form known in the art, and D the feed hopper arranged under the outlet E of the receptacle for the combustible. The

rest of the receptacle itself is not represented in the drawings but is to be thought of as located above the outlet E.

I arrange thc receptacle for the combustible and the feed mechanism, which is more particularly described hereinafter, stationary, in contradistin'ction to the third known arrangement referred to above in which the movable electrode serves as receptacle for the combustible. This is very important,

because in thisl manner I make the regulating devicel independent ofA the constantly varying weight of the quantity of combustible and diminish the amount of energy of the lamp requisite'for its regulation, as only the feed mechanism has to be moved. In addition, without altering the regulating mechanism I can put any desired quantity of combustible into the lamp; also, considerable changes in the specific weight of the combustible require onlv immaterial. if any, changes in the regulatingmechanism. further radvantage of this arrangement is that. owing to the receptacle being at rest and in spite of the electrode supplying the combustible being. movable, almost any of the well known conveying and feeding devices mav be employed for discharging the combustible from the receptacle.

In the drawings the'following are indi-` cated as the most useful arrangements: In 141g. 1 a feed-wheel f, 1n Fig. 3 a conveyer screwm, as well as a hopper d having a tapper t, but equivalent feeding means known in the art maybe employed. The arrangement of the feed hopper d having a tapper according to Fig. 3 is particularly suitable, because the hopper itself can serve as storage receptacle,V and the means for causing discharge therefrom consists only of the small hammer t.' An ordinary `butterfly valveY u suffices here for regulating the outflow, while in the othercases 'the regulation of the outflow is more difficult. vFor operv ating the tapper I provide a. relay r2 and a spring e which actuate a rocking armature 82 carrying the Ahammer t; The coil rg 1S connected to the points F and G and is energizzed simultaneously with the relay 1', which is described hereinafter; it may, of course, be connected in series with the relay r1.

The combustible may be supplied by the feeding mechanism to the arc either through the electrodes, or through a tube or channel vleading laterally of the electrode to the arc.

ably comprise a funnel '7c which surrounds the top electrode with about 1 vto 3 mm. clearance-immediately above the arc and is simultaneously formed as a so-called economizer. There is no danger of the funnel becoming stopped up at j because the electrode is constantly in motion. Y

The feeding mechanism shown-in Fig. 1 is actuated periodically, with the intermediary of the movable electrod'e,I according to vmy invention by means of a pawl secured to said electrode. this pa/wl may act on the feeding mechanism by direct engagement .with it or it may indirectly release mechanical or electromechanical auxiliary devices (not shown). Fig.` 1-shows'the direct engagement. In this form the funnel D carries an arm e havinga pawl e, which engages the blades i. of t e feed-wheel f when the electrode B descends and thus rotates the wheel clockwise step bv step. In this manner the required quantity' of combustible is thrown out of the receptacle E A 'through the outlet g. A yieldinglv supported retaining pawl c engaging behind blades h after each stroke prevents reverse movement of the wheel, and by the elasticity of its yielding support also prevents overthrowing.

The above simplest form of regulation, but it increases described direct drive is the v the consumption of current in the lamp bel cause a considerable amount of power is vnecessary for driving the feeding mecha-v nism. By employing mechanical or electromechanical auxiliary devices the movable electrode is materially relieved; it then moves vonly a small releasing lever or 'a switch, which in vturn controls a clockwork or a relay, fed from the electric supply system. In this manner the current cons ump- Vtion of the lamp itself'and the load on the main coil of the lamp is reduced, and also greater freedom -of movement of the movi fable electrode is materially increased and thereby the sensitiveness of the lamp to regulation: in addition., it ispossible to place any desired amount of auxiliary sources of power for moving the feeding mechanism ias 0 on the beveled surface.

into control of such mechanism. This arrangement is illustrated in Fig. 3. The feed screw m is operated by a relay r, comprising an armature s, which carries a bent arm w which forms the feeding pawl for ratchet wheel e. This wheel is secured on the shaft of the worm m and prevented from overthrowing by retaining pawl li.. The relay fr, is energized as soon as a stop or abutment n,-

which is secured on but insulated from the electrode B, depresses `the lever 0 which is located in its track and thereby opens the contactat H between the two electrically conducting parts p and g'of the switch C. The abutment n as will be clear from F ig. 3 is beveled at its end with which it cooperates with lever 0, also beveled, but in the opposite direction. When abutment n on descending depresses the rear end of lever o to break the contact at H, it -will on descending far enough, eventually slide past lever 0, so that the latter falls back into normal position. Abutment a. descends past lever o when the lamp is at rest where the electrodes contact. Then if the lamp is lighted and electrode B drawn upward to form the arc, abutment m. can slide past lever So long as there is st uliicient combustible at the arc, the latter is regulated by the upward and downward movement ofthe electrode B as usual, without thereby causing the feeding of combustible. However, as the latter is consumedthe electrode gradually sinks lower and lower until abutment n engages with and depresses lever o, 7), lifting it for al moment at H, which sends a current impulse through re-l lays 71 and zal. This in turn operates the feeding 'mechanism and the necessary amount of combustible supplied thereby causes electrode B to again rise, abutment n thereby rising from lever o. The switch arm p is insulated from the member o. The

relay is then energized inthe following cirv cuit: positive feeder l, electrodes A, B and the arc therebetween, conductor 2, lamp coil C, conductors 3, 4, relay rnconductor 5 and negative feeder G. The shortcircuiting con' -nection by way of the parts 79, q is provided for preventing the relay coil being permanently energized and the loss kof energy caused thereby. Consequently, the relay coil is generally shunted and is only energized at the time of, and for the purpose of, regulation.

As material for the electrodes A. and B,

-according to tests which have been made plying current may be so arranged that they are consumed to only a small extent when .cannot be helped.

the lamp burns. The top electrode may, if desired, be made of copper with a liberal section of area. Copper' as electrode, however, emits but little light owing to its good conductivity, which keeps the temperature of the arc low. For this reason substances which of less heat conductivity are preferable as electrodes, and if necessary such substances may have metal insertions :1; (Fig. 3) for increasing the electrical conductivity, -which insertions must be limited however to the absolutely necessary amount.

With regardto the bottom electrode in a lamp having vertically superposed carbons, care should be taken that this current-supplying member has'a larger cross-section than the top current-supplying member, first /in order that the combustible which is 'thrown out does not fall past it, and second,

in order that whatever portion of the electrode may be consumed by combustion may burn away with as fiat a tip as possible. Bottom` electrodes which ldo not readily burn away are preferably filed flat or hollowed out like a trough as shown at v/. in

used as lower electrode the burning flat will .i l

be aided by having it copper-plated, as in dicated at Z in Fig. 3. lVhen the means for supplying current to the arc is used as catch plate it must be connected to the positive pole of the system, as shown in Fig. 3.

As powdered combustible, both pure carbon may be used and any desired mixture oi carbon with other substances which emit strong light, such as metallic salts and the like. A lamp according to my invention constitutes a very simple apparatus for use in testing the strength of light and the eli'ect of various kinds of combustibles. Diliferent kinds of combustibles may be mixed in thc lamp itself. since several devices Jfor sup'- plyingcombustible can be combined in it without diiiiculty, such a combination beingr shown in Fig. 3, in which the arrangements described above with reference to Figs. l and 2 are employed simultaneously.

Instead of pouring the combustible to the arc as described above, it might be injected or `blown* into it. Neither of such modes ol' operation can be. recommended. however. Pouring it has the very great advantage that the arc is not'disturbed, whereas in the other methods referred to disturbance ot the arc The method of pouring is used to best advantage when, as shown. superposed electrodes and a tubular upper for lll)

electrode areemployed and the combustible ispoured through the middle of the latter onto the birttom electrode. For, owing to the tubular shape of the electrode, the arc occupies the position represented in Figs. l and Il namely, it is located so fai' to one side that the descending 'combustible does not disturb it. The fallen combustible is first fused and then gradually vaporized, and assumes the form of vapor only in the arc.

l claim:

1. ln an electric arc-lamp of the character described, the combination, with an electrode, of a movable electrode, a receptacle containing a combustible, feeding means for supplying the combustible to between said electrodes for maintaining an arc therebetween. means for moving said movable electrode in dependence on the lelectrical occurrences in the lamp, and means for actuating said feeding means in dependence on the coi-isuniption of combustible in the arc.

L). In an electric arc-lamp of the characterl described, the combination, with an electrode, of a movable electrode, a i'eceptacle containing a combustible, feeding means for sup'plyingthe lcombustible to between said electrodes for maintaining an arc therebe-- tween, means for moving said movable elecl trode in dependence on the electrical occurrences in thelamp, and means for actuating said feeding means in dependence on lthe length lof the arc.

3. In an electric arc-lamp of the character described, the combination, with anL electrode, of a movable electrode, areceptacle containing a combustible, feeding-means for supplying the combustibleto between said electrodes for maintaining an arc therebetween, means for moving said movable electrrde. in dependence on the electrical occurrences in the lamp, and means for actuating said feeding means in dependence on the position of the movable electrode.

4. In an electric arc-lamp of the character described` the combination. with an electrode, of-a movable electrode, a. fixed receptaclel containing. a combustible, feeding mechanism fixed in the lamp for sul'iplying the combustible through said movable electrode to betweensaid electrodes for maintaining an arc therebetween, means for actuating said feeding mechanism in depend- A ence. on the consumption ofcombustible in the are, and means for moving said movable electrode in dependence on the electrical oc,-

currences in the lamp. l ,5. ln an electric'arc-lamp of the character de.-:cribed, the combination, with an electrode` of a movable electrode, 'a receptacle eontainiuga combustible fixed in the lamp, feeding mechanism fixed-in 4the lamp for supplying the combustible to between said electrodes for maintaining an arc therebetween, means attached to said movable electrode for periodically actuating said feed-' ing mechanism, and means for moving said movable electrode' in dependence on the electrical occurrences in the lamp.

6. In an electric arc-lamp of the characcombustible, feeding means for supplying the combustible by way of said economizer to between said electrodes for maintaining an arc therebetween, and means for. moving saidmovable electrode in dependence ontheelectrical occurrences in the lamp.

7. In an electric arc-lamp of the` character described, the combination, with an electrode, of a movable electrode arranged over the same, a funnel-shaped cconomizer sur-y rounding the movable electrode with clearance, a receptacle containing a combustible, feeding means for` supplying the combustible by way of said economizer to between Said electrodes for maintaining an arc therebetween, and means for moving said movable electrode in dependence'on the electrical occurrences in the lamp.

8. ln an electric a rc-lamp of the character described, the combination, wi-th anelec-l trode, of a movable electrode,'a funnell shaped economizer surrounding the movable electrode' with clearance, a hopper, containing-a combustible,4 for supplying the latter electrodes for maintaining an arc therebetween, a tapper for knocking said hopper, electromagnetic means for actuating said tapper in dependence on the electrical occu'rrences in Vthe lamp, and means formoving f said movable electrode in dependence on the 9. vTn an electric arc-lamp of the 'character described, the combination. with an electrede. of a movable electrode, a'receptacle containing a combustible fixed in the lamp,

feeding mechanism fixed in the lamp for supplying the combustible to between said electrodes for maintaining an arc therebetween, nfeans comprising a stop attached to said movable electrcde,-a switch actuated bv said stop, a relay controlled by said switch for 'periodically actuating said feeding mechanism, and means for moving said movable electrode in' dependence on the electrical occurrences in the lamp.

10. In an electric arc-lamp of the character described, the combination, with an electrode, of 'a movable electrode, a receptaclecontaining a combustible fixed in the lamp, feeding mechanism fixed in the lamp by way of said economizerto between said for supplying the combustible to between said electrodes for maintaining an arc therebetween, means comprising a stop attached to said movable electrode, a switch actuated b y said stop, a relay controlled by said switch for periodically actuating said feeding mechanism, said relay being normally sliort-circuited by said switch, and means for moving said'movable electrode in delamp.

ln testimony whereof I have signed my name to this specification in the presence of two Witnesses.

l y RCHARD HOLSTEN. Witnesses:

HENRY HASPER, WOLDEMAR HAUPT.

pendence on the electrical occurrences in the La 

